An automotive vehicle generally has an odometer allowing the total distance that this vehicle has covered to be known. However, this counter provides no information on the distance covered by each tire of the vehicle.
For example, when tires are changed temporarily (for example in winter, when snow tires are put on) or when old worn-out tires are replaced, the distance displayed by the odometer no longer indicates the distance actually covered by the tires.
Conventionally, the only indication of the distance covered by a worn tire is thus the wear to its tread.
Tire manufacturers have thus had the idea of inserting a device which is one piece with the tire and inside the latter and which indicates the distance covered by this tire. Such devices already exist.
Of these devices, U.S. Pat. No. 5,877,679 discloses a device for counting the rotations of a tire on a vehicle, comprising a rigid casing, connection means intended to connect the casing mechanically to the inner surface of the tire, and a sensor intended to generate an electrical signal on each rotation of the wheel, in which the connection means comprise at least two mounting blocks which are offset from one another and the sensor is a force sensor arranged between the two mounting blocks.
The existing devices have a limited service life, however, since they have a high level of power consumption and are complex.